[libcamera-devel] [PATCH v3 2/3] qcam: Add a GUI way to use capture script

[Kieran Bingham]

Quoting Utkarsh Tiwari via libcamera-devel (2022-06-27 04:01:58)
> Implement an Open Capture Script button which would allow the user
> to open a Capture Script (*.yaml).
> This button has two states Open and Stop.
> 
> Open state allows user to load a capture script.
> When clicked in open state present them with a QFileDialog
> to allow user to select a single file.
> 
> Stop state stops the execution of the current capture script.
> 
> Introduce a queueCount_ to keep track of the requests queued.
> 
> When stopping the execution no count is reset and the
> capture continues as it is.
> 
> Requests are queued with any controls the script matching
> the current queueCount_
> 
> Signed-off-by: Utkarsh Tiwari <utkarsh02t at gmail.com>
> ---
>  src/qcam/assets/feathericons/feathericons.qrc |  2 +
>  src/qcam/main_window.cpp                      | 66 +++++++++++++++++++
>  src/qcam/main_window.h                        |  6 ++
>  src/qcam/meson.build                          |  2 +
>  4 files changed, 76 insertions(+)
> 
> diff --git a/src/qcam/assets/feathericons/feathericons.qrc b/src/qcam/assets/feathericons/feathericons.qrc
> index c5302040..6b08395a 100644
> --- a/src/qcam/assets/feathericons/feathericons.qrc
> +++ b/src/qcam/assets/feathericons/feathericons.qrc
> @@ -3,9 +3,11 @@
>  <qresource>
>         <file>aperture.svg</file>
>         <file>camera-off.svg</file>
> +       <file>file.svg</file>
>         <file>play-circle.svg</file>
>         <file>save.svg</file>
>         <file>stop-circle.svg</file>
>         <file>x-circle.svg</file>
> +       <file>x-square.svg</file>
>  </qresource>
>  </RCC>
> diff --git a/src/qcam/main_window.cpp b/src/qcam/main_window.cpp
> index adeb3181..e133b618 100644
> --- a/src/qcam/main_window.cpp
> +++ b/src/qcam/main_window.cpp
> @@ -20,6 +20,7 @@
>  #include <QImage>
>  #include <QImageWriter>
>  #include <QInputDialog>
> +#include <QMessageBox>
>  #include <QMutexLocker>
>  #include <QStandardPaths>
>  #include <QStringList>
> @@ -232,6 +233,13 @@ int MainWindow::createToolbars()
>         saveRaw_ = action;
>  #endif
>  
> +       /* Open Script... action. */
> +       action = toolbar_->addAction(QIcon::fromTheme("document-open",
> +                                                     QIcon(":file.svg")),
> +                                    "Open Capture Script");
> +       connect(action, &QAction::triggered, this, &MainWindow::chooseScript);
> +       scriptExecAction_ = action;
> +
>         return 0;
>  }
>  
> @@ -255,6 +263,58 @@ void MainWindow::updateTitle()
>         setWindowTitle(title_ + " : " + QString::number(fps, 'f', 2) + " fps");
>  }
>  
> +/**
> + * \brief Load a capture script for handling the capture session.
> + *
> + * If already capturing, it would restart the capture.
> + */
> +void MainWindow::chooseScript()
> +{
> +       if (script_) {
> +               /*
> +                * This is the second valid press of load script button,
> +                * It indicates stopping, Stop and set button for new script.
> +                */
> +               script_.reset();
> +               scriptExecAction_->setIcon(QIcon::fromTheme("document-open",
> +                                                           QIcon(":file.svg")));
> +               scriptExecAction_->setText("Open Capture Script");
> +               return;
> +       }
> +
> +       QString scriptFile = QFileDialog::getOpenFileName(this, "Open Capture Script", QDir::currentPath(),
> +                                                         "Capture Script (*.yaml)");
> +       if (scriptFile.isEmpty())
> +               return;
> +
> +       /* If we are already capturing,
> +        * stop so we don't have stuck image in viewfinder. */

Our coding style uses block quotes with /* and */ on their own lines.

	/*
	 * If we are already capturing, stop so we don't have a stuck
	 * image in the viewfinder.
	 */

What causes a stuck image? Is it while the script is being loaded and
parsed?

It seems reasonable to stop as we're going to have to do a restart
anyway.


> +       bool wasCapturing_ = isCapturing_;

Local variables don't use the _ at the end. That signifies that the
variable is a class variable.

With those fixed, you can add:


Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> +       if(isCapturing_)
> +               toggleCapture(false);
> +
> +       script_ = std::make_unique<CaptureScript>(camera_, scriptFile.toStdString());
> +       if (!script_->valid()) {
> +               script_.reset();
> +               QMessageBox::critical(this, "Invalid Script",
> +                                             "Couldn't load the capture script");
> +               if(wasCapturing_)
> +                       toggleCapture(true);
> +               return;
> +       }
> +
> +       /*
> +        * Valid script verified
> +        * Set the button to indicate stopping availibility.
> +        */
> +       scriptExecAction_->setIcon(QIcon(":x-square.svg"));
> +       scriptExecAction_->setText("Stop Script execution");
> +
> +       /* Start capture again if we were capturing before. */
> +       if(wasCapturing_)
> +               toggleCapture(true);
> +}
> +
>  /* -----------------------------------------------------------------------------
>   * Camera Selection
>   */
> @@ -510,6 +570,7 @@ int MainWindow::startCapture()
>         previousFrames_ = 0;
>         framesCaptured_ = 0;
>         lastBufferTime_ = 0;
> +       queueCount_ = 0;
>  
>         ret = camera_->start();
>         if (ret) {
> @@ -789,5 +850,10 @@ void MainWindow::renderComplete(FrameBuffer *buffer)
>  
>  int MainWindow::queueRequest(Request *request)
>  {
> +       if (script_)
> +               request->controls() = script_->frameControls(queueCount_);
> +
> +       queueCount_++;
> +
>         return camera_->queueRequest(request);
>  }
> diff --git a/src/qcam/main_window.h b/src/qcam/main_window.h
> index c3e4b665..2cdf7169 100644
> --- a/src/qcam/main_window.h
> +++ b/src/qcam/main_window.h
> @@ -26,6 +26,7 @@
>  #include <libcamera/request.h>
>  #include <libcamera/stream.h>
>  
> +#include "../cam/capture_script.h"
>  #include "../cam/stream_options.h"
>  #include "viewfinder.h"
>  
> @@ -86,11 +87,14 @@ private:
>         void processHotplug(HotplugEvent *e);
>         void processViewfinder(libcamera::FrameBuffer *buffer);
>  
> +       void chooseScript();
> +
>         /* UI elements */
>         QToolBar *toolbar_;
>         QAction *startStopAction_;
>         QComboBox *cameraCombo_;
>         QAction *saveRaw_;
> +       QAction *scriptExecAction_;
>         ViewFinder *viewfinder_;
>  
>         QIcon iconPlay_;
> @@ -124,6 +128,8 @@ private:
>         QElapsedTimer frameRateInterval_;
>         uint32_t previousFrames_;
>         uint32_t framesCaptured_;
> +       uint32_t queueCount_;
>  
>         std::vector<std::unique_ptr<libcamera::Request>> requests_;
> +       std::unique_ptr<CaptureScript> script_;
>  };
> diff --git a/src/qcam/meson.build b/src/qcam/meson.build
> index c46f4631..67074252 100644
> --- a/src/qcam/meson.build
> +++ b/src/qcam/meson.build
> @@ -15,6 +15,7 @@ endif
>  qcam_enabled = true
>  
>  qcam_sources = files([
> +    '../cam/capture_script.cpp',
>      '../cam/image.cpp',
>      '../cam/options.cpp',
>      '../cam/stream_options.cpp',
> @@ -37,6 +38,7 @@ qcam_resources = files([
>  qcam_deps = [
>      libatomic,
>      libcamera_public,
> +    libyaml,
>      qt5_dep,
>  ]
>  
> -- 
> 2.25.1
>